Problem: Simplify the following expression: $t = \dfrac{-2r}{2} - \dfrac{10r}{2}$
Solution: Since the expressions have the same denominator we simply combine the numerators: $t = \dfrac{-2r - (10r)}{2}$ Combine like terms: $t = \dfrac{-12r}{2}$ Simplify by dividing numerator and denominator by 2: $t = \dfrac{-6r}{1}$ $t = -6r$